Device for regulating the delivery of reciprocating compressors



F. VOLLM ER DEVICE FOR REGULATING THE DELIVERY OF RECIPROCATING COMPRESSOR S Filed Aug. 10 1943 INVENTOR fk/rz VOLLME/E ATTORNEYS Patented July 3, 1945 DEVICE FOR REGULATINGTHE" DELIVERY ,1 1 1 j or'nncn nooa'rme ooMPnnssons Fritz voumer, ZurichJSwitzer-land Appiicanonnugusrm, 1943, Serial in). 498,940 TCla im s. .(plfisjiQrim f The invention relates to a suction valveihaving a valve plate for regulating the delivery of;

reciprocating compressors;

"whichfis firmly connected to the hub 8 and the The suction valve of the present invention comprises a casing with a valve-plate actuatin member therein having means actingppon a? valve plate so as to open it, andmeans DIQYiding a gap between the valve-plate! actuating member and thegcasing by means of whichthe loading of the suction valve is relieved in ac cordance with the return flow.

The invention presents the advantage for suetion valves that the return forces are not exerted on the valve plate, with the result that the suction valve can be designed so as to be best suited to stream-line requirements. 'Nor is the most sensitive member of the suction valve, the valve plate, any longer loaded by. the controlling forces. In particular, when the gap has a nozzle-like design, considerable forces .can be employed for the controlling process, in spite of the factthat flow losses during the suction stroke are, extremely small, because the coefilcient of contraction of the gap is considerably-greater for the return thanfor the suction flow.

Examples of execution of the subject matter of the invention are represented diagrammatically in the drawing.

Fig. 1 shows, a partial longitudinal section through a suction valve of the invention.

Fig.2 shows another suction valvehaving a gap with a nozzle-shaped construction.

Fig. 3 ispa View of the suction valve of Fig. 12

with the parts in a different position.

Fig. 4 illustrates characteristics of the compressor for various settings of thevalve-plate actuating member.

Fig. 5 shows another form of suction valve.

of the invention.

In Fig. 1, the suction valve of a reciprocating compressor not otherwise shown has a valve 3 by light springs 2 (Fig. 2 which take the weight of plate I. i i

The means for holding open the valve plate I consists of rods 5 which are attached to plate 6. The plate 6 is guided bya hub 8 surrounding a bolt 1 and is pressed upwards against a shoulder ID of bolt 1 by a spring 9. A spring H is 10 "tio stroke; of the compressor meets with no re-- sis tance to itsfiow worthy of mention andlits rods 5, and a gap l9 formed between the plates I1 and the ring [8 provided on the valve casing lSQB y bending down the edges of theplate and 'ring the gap is designed in the form of a nozzle pointing towards the valve plate.

As a result of this ,nozzle-shapedgap IS the mediumfiowing therethrough duringjthe sucpressure is thus not decreased. Medium flowing back from the valve plate, on the other hand, is effectively throttled by the eddies arising at the edges of parts I! and I8.

In Fig. 2 the suction valve is shown with its movable parts in a position ofirest. The valve plate I closes at the beginning of the pressure stroke and compression begins in the compressor at a in Fig. 4.

In Fig. 3 the spring plate l2 has been lowered so far by screwing down handwheel l3 that the force of spring ll exceeds that oi spring 9, and the rods 5 press down valve plate I. During the compression stroke the medium to be compressed is forced back out of the compressor cylinder through the open suction valve and flows through subjected to this pressure overcomes the excess force of spring ll over spring 9 and presses the hub. 8 of the valve-plate actuating member against shoulder l0.

The rods 5 then free the valve plate I, which thereupon presses against the seat 3 and closes the cylinder during the compression stroke at plate I which is pressedagainst the valve seat one of the points 11, c or d (Fig. 4) after which compression begins in the compressor. As a result of the increase in pressure during compresslon, .the valve plate I remains closed,as the excess force of spring II is no longer sufficient to keep the valve open. V

In Fig. 5 the suction valve has a plate 2| at tachedto the wall l5 of the valve casing, independently of the control device. The valve-plate actuating member has a lower spring plate 22 which surrounds bolt 1 inthe form of a kind of j cap and carries the rods 23. The flared shape of the inner edge of member 2| results in a throttling of the return flow in gap 24 and causesin space 20 an increase of pressure which loads the J spring plate 22 and overcomes the force of spring I I, so that valve plate I is released and can press 66 against the seat 3'.

suction valve has a plate I'll 1. Suction valve for regulating the delivery of reciprocating compressors which comprises an exterior housing, a valve casing mounted in the housingwith a :space "between the housing land the casing for the flow of gas, a valve seat arranged transversely across the valve casing, pasw v valve seat on which the valve-plate actuating sages in the valve seat, avalv'e plate with resilient closing means pressing the valverplate against the valve seat, a valve-plate actuating-member slidably supported within the casing, spring means opposing the movement of "the valve plate actuating member in both directions-from-axcertain position, means on :the valve-plate actuatin member for moving the valve plate away from its seat to open the passages in --the valve seat for the flow of gases therethrough inao'ne direcvtion, means for adjusting the springs opposing the movement of.the valveaplateactuating.mem-

(her to cause it .to respond to difi eren t gas pressures, and means providing a restricted. gap. be-

tween the valve-.plateactuatingmemberand .the I .valve-ecasingefor, the flow of gas ,therethrough in the oppositedirection. I s

.,.2.. A Suction valve according to claimll wherein .thengap is of nozzle-shaped construction between the valve-plate actuating member and the casing, whereby the gas flowing therethrough in said opposite direction meets little resistance whereas the gas flowing in the first mentioned direction creates eddies and is throttled. 3. .A suction valve according to claim 1 wherein the valve-plate actuating member includes a plate with the peripheral edge turned down to form with the casing a gap of a nozzle-shaped con- :struction. 1 4. Asuction valve according to claim 1 which comprises rigid guide means connected to the -rmember-is slidably-supported.

:5. fA suction' valve according to claim 1 in which the valve-plate actuating member includes a lat erallyprojecting plate slightly spacedfrom the rcasing whereby said gap is in the form of an annular passage.

*6. Asuction valve according to claim 1 in which the "valve seat has a plurality of vholes therethrough and the valve-plate actuatingmember has a plurality of rods slidable in the holes for engaging the valve plate to open the valve.

Asuction valve accordingto claim 1 inwhich thecasingrhas .azplateattached thereto which hasan inner edge slightly spaced from the valveplate; actuating member whereby said gap is .in

the form ,ofan annular passage.

. FRITZ v LLMER. 

